1. Field of the Invention
This invention relates to flush assemblies for toilets. More particularly, the invention relates to a means which prevents opening of the water inlet valve to the toilet flush tank until a flush cycle is deliberately initiated, thereby preventing continued loss of water from the flush tank in the event there should be a leak from the tank caused, for example, by a malfunction in either the water inlet valve or the water outlet valve from the tank.
2. Description of the Prior Art
A large variety of toilet flush assemblies are known in the prior art. Most of the toilet flush assemblies currently in use, especially in residential applications, utilize a float assembly to control opening and closing of the water inlet valve to the flush tank. When a flush handle is operated to open the flush valve for releasing water from the tank, the float drops, permitting a water inlet valve to open to enable water to flow into the tank and refill it. As the level of water in the tank rises, the float also rises and eventually shuts off the water inlet valve, precluding further flow of water into the tank. However, it is not uncommon for a leak from the tank to develop, e.g., past the water outlet valve, whereby the level of water in the flush tank gradually falls, resulting in lowering of the float and opening of the water inlet valve to introduce more water into the flush tank. This cycle repeats continuously so long as the leak remains unrepaired. Over time, a substantial amount of water is wasted.
Most people repair these leaky toilets as soon as they are discovered. However, some leaks may not be readily apparent, or a needed repair may not be made for other reasons, with the result that a substantial amount of water is lost through leaky toilets.
Numerous solutions have been offered in the prior art to prevent continued loss of water in the event that a leak should develop from a toilet flush tank. Examples of such efforts are shown in the patents submitted with the information disclosure statement filed herewith. These prior art systems provide means which act on the float to prevent the float from moving to open the water inlet valve except when a deliberate flush cycle is initiated. However, these prior art systems are relatively complicated and expensive in construction, and some of them may not be reliable in operation. Many of them also require extensive modification of the conventional flush system, and cannot be conveniently retrofitted into existing systems.
Moreover, since the prior art systems work by retaining the float in an elevated position, they are incapable of functioning to prevent continued leakage if the float never returns to its elevated position. These prior art systems therefore cannot prevent leakage of water from the flush tank in the event of a catastrophic failure of the flush outlet valve, or leakage of water into the float, or other eventuality which prevents return of the float to its normal elevated position, or even a malfunction in the usual water inlet valve.
Accordingly, there is need for a simple and inexpensive means which is reliable in operation and which prevents continued loss of water in the event of leakage from a toilet flush tank. There is also need for such a device which prevents continued loss of water in the event of a catastrophic failure of the flush outlet valve, or other cause for failure of the float to return to its elevated position for closing the water inlet valve.